Behavior of Yb³⁺ and Er³⁺ during Heat Treatment in Oxyfluoride Glass Ceramics

Figure 11

Temporal evolution of the upconversion emission at 660 nm with obtained exciting at 975 nm for SA1.8EY and SA2.18EY samples heat treated at 630, 660, 675, and 690°C for 48 h.

(a)

(b)